// ECMAScript 2016

// Array.prototype.includes
/* const arr = ["foo", 1, NaN, false];
console.log(arr.indexOf("foo"));
console.log(arr.indexOf(NaN)); // indexOf方法不能查找到NaN数据
console.log(arr.includes(NaN), arr.includes("foo")); */

// 指数运算符
console.log(8 ** 2, Math.pow(8, 2));
